Paris, France: Low levels of vitamin D can trigger hypertension, according to the world's largest study to examine the causal association between the two. Although observational studies have already shown this link, a large-scale genetic study was necessary before the cause and effect could be proven, the annual conference of the European Society of Human Genetics (ESHG) will hear today (Tuesday).

Dr. Vimal Karani S, from the Institute of Child Health, University College London, London, UK, will tell the meeting that data from the D-CarDia collaboration, involving 35 studies, over 155,000 individuals, and numerous centres in Europe and North America, showed that those with high concentrations of 25-hydroxyvitamin D (25(OH)D) had reduced blood pressure and therefore a reduced risk of hypertension. "We knew from earlier observational studies that low 25(OH)D concentrations were likely to be associated with increases in blood pressure and hypertension, but correlation is not causality", he says. "Additionally, randomised controlled trials of vitamin D supplementation in humans have produced inconsistent effects on cardiovascular outcomes. The whole picture was somewhat confused, and we decided to try to figure it out once and for all."

The researchers used genetic variants known as single nucleotide polymorphisms, or SNPs*, as proxy markers to reflect individual's vitamin D status in order to test for a causal association with blood pressure and hypertension. When the results were analysed, they found a significant link; for every 10% increase in 25(OH)D concentrations, there was a 8.1% decrease in the risk of developing hypertension.

"Even with the likely presence of unobserved confounding factors", Dr. Karani S will say, "the approach we followed, known as Mendelian randomisation, allows us to draw conclusions about causality because the genetic influence on disease is not affected by confounding. To put it in simple terms, by using this approach we can determine the cause and effect and be pretty sure that we've come to the right conclusion on the subject."

Low vitamin D status is common throughout the western world, the researchers say, and hence these data have important public health implications. The best-known manifestation of vitamin D deficiency is the childhood bone disease rickets, where long bones are weakened by the deficiency and start to bend. Recently, however, Vitamin D has been implicated in a number of other non-skeletal-related conditions, but studies involving supplementation have given conflicting results.

"Our study strongly suggests that some cases of cardiovascular disease could be prevented through vitamin D supplements or food fortification", says Dr. Karani S. "Our new data provide further support for the important non-skeletal effects of vitamin D. We now intend to continue this work by examining the causal relationship between vitamin D status and other cardiovascular disease-related outcomes such as lipid-related phenotypes, for example, cholesterol, inflammatory markers such as C-reactive protein, and type 2 diabetes and markers of glucose metabolism. We believe that we still have a lot to find out about the effect of Vitamin D deficiency on health, and we now know that we have the tools to do so."

I have to take two blood pressure depressors. One of them has been very expensive (but recently went generic), but works cooperative to modify the cheaper one. The warning on it says "Prolonged or excessive exposure to direct and/or artificial sunlight should be avoided while taking this medication." So no vitamin D from sun. Go figure.

(For another reason, I have been self-medicating with vitamin D3 every day, for mental attitude and calcium uptake. Whew!) My physician also suggested to take fish oil (Omega-3) and 1 aspirin every day.

The story: Take one medicine. Then another to modify the first. Then another because of the first two. Then more because of those. Etc, etc, etc?

“My doctor told me that many people with high BP have lower BP in the summer, so maybe its, in part, the Vit. D from the sun.”

You also tend to lose more salt and water in warmer weather, and your peripheral vasculature dilates when it is warm (to accommodate heat loss). So, like most things in biology and medicine, it's multifactorial.

I had to have my colon out. The colon is where vitamins D,E, A, and K are absorbed. My GP always tells me my D3 is low and so I increase my oral intake. I get in sun in summer but i have very little pigment and prone to bad sun burn. Putting sun screen on defeats purpose of getting D3 from sun. My question: you think it is ok to just overload on oral D3? I take 6000 now

Jun 2, 2012 ... Salt consumption is said to raise blood pressure, cause .... These covered some 100,000 people in more than 30 countries and showed that salt ... raising it is a shill for the food industry and doesn’t care about saving lives.

I had to have my colon out. The colon is where vitamins D,E, A, and K are absorbed. My GP always tells me my D3 is low and so I increase my oral intake. I get in sun in summer but i have very little pigment and prone to bad sun burn. Putting sun screen on defeats purpose of getting D3 from sun. My question: you think it is ok to just overload on oral D3? I take 6000 now

The small intestine, mostly the jejunem and ileum, is where vitamins D, E, A, and K, the fat soluble vitamins, are absorbed. The large intestine, the ascending, transverve, descending and sigmoid colon, mostly helps to maintain water and electrolyte homeostasis in conjunction with the kidneys. Consider a fecal fat test to rule out fat malabsorption.

Blood pressure is determined by two parameters, cardiac output (the amount of blood pumped by the heart per minute) and the resistance in the peripheral vasculature. It's really not very different than a plumber thinking about the pressure in pipes of a certain diameter with a specific flow rate.

There are a lot of things that can increase vascular resistance (e.g. specific circulating factors that affect the contractile state of the small muscular blood vessels that determine vascular resistance), and a lot a ways cardiac output can be affected, including increased blood volume secondary to salt intake in susceptible individuals.

The bottom line is that it is complex, and there are a lot of different reasons people can have high blood pressure. The sensitivity to salt intake is definitely affected by genetics. There are rats that get high blood pressure when exposed to dietary salt, but normal rats don't.

Anyway, I agree with you that salt probably doesn't have much of an effect on people with normal baseline blood pressure. There are those who have to think about this though.

“The bottom line is that it is complex, and there are a lot of different reasons people can have high blood pressure. The sensitivity to salt intake is definitely affected by genetics. There are rats that get high blood pressure when exposed to dietary salt, but normal rats don’t.”

That is the key not knee jerking/banning of salt with any patient with some hbp based on economic greed not scientific double blind studies.

I wish I could have the net profit from just one days movement of salt free/low salt additives and food. That would provide income for decades for generations of my current family and those not here yet

15
posted on 06/12/2013 8:29:07 AM PDT
by Grampa Dave
('How empty and dead' were they to let Chris Stevens, one of them , die for 'Obama-Clinton fiction?')

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